Enhance installation timeout error message

When an installation times out (which can also be because the download itself took too long), we should direct users to try changing the default installation timeout. Our error experience should be something like this:

```ts
if (reason && reason.message === timeoutConstants.timeoutMessage)
{
await window.showErrorMessage(
`Timed out after ${this.timeoutValue} seconds while installing the .NET Runtime. You can increase this timeout by changing the 'dotnetAcquisitionExtension.installTimeoutValue' setting to a longer duration.`,
"Go to setting"
).then(selection => {
if (selection == "Go to setting") {
commands.executeCommand("workbench.action.openSettings", "dotnetAcquisitionExtension.installTimeoutValue");
}
})
}
```

in a suitable location. This will show a button that, when clicked, will take the user directly to the setting we specify.